Abstract: How to optimize the content of brand social media advertising is a hot issue in academia.Based on the involvement theory and the characteristics of social media,this study defines the four dimensions of consumer social media participation:consciousness,emotion,rational thinking and identity.After collecting second-hand data,variance model is used to analyze the impact of brand social media advertising content on consumers' social media participation.The results show that the type of social media advertising content has a significant impact on consumers' social media involvement,and new product content has the best effect,followed by promotion,game/lottery and social responsibility content.This study not only enriches the theoretical research of brand social media advertising from the perspective of consumer behavior,but also provides valuable management suggestions for brand design of social media advertising content marketing.

Key words: brand advertising, social media, content marketing, consumer nvolvement